“It’s a scam,” says George Hotz, whose company Comma.ai Inc. makes a driver-assistance system similar to Tesla Inc.’s Autopilot. “These companies have squandered tens of billions of dollars.” In 2018 analysts put the market value of Waymo LLC, then a subsidiary of Alphabet Inc., at $175 billion. Its most recent funding round gave the company an estimated valuation of $30 billion, roughly the same as Cruise. Aurora Innovation Inc., a startup co-founded by Chris Urmson, Google’s former autonomous-vehicle chief, has lost more than 85% since last year and is now worth less than $3 billion. This September a leaked memo from Urmson summed up Aurora’s cash-flow struggles and suggested it might have to sell out to a larger company. Many of the industry’s most promising efforts have met the same fate in recent years, including Drive.ai, Voyage, Zoox, and Uber’s self-driving division.